In the next algoritm I made two set data (NFW1tbcx.dat and SIS1tbcx.dat) with which I make two different plots and I need to make a third plot that would be the difference of the previous two, so the easy path is take both set data and obtain the diference between them making a new data file which will be plotted. Lets start with the algoritm.

As you can see both are totally diferent shape, but I need a new plot defined like, lets say plot Red - Plot Black

My first try to do this "diference between those two plots" is using the command Transpose like this thread suggest using NFW1tbcx.dat and SIS1tbcx.dat to get a new file dat called DIFNFWSIS1, and the plot that new file, like this

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